Law enforcement personnel and private investigators conduct surveillance activities on people in order to document their specific activities. For the most part, a large volume of surveillance is conducted in the area of “rolling surveillance”. This type of surveillance is where the agent sits in a motor vehicle and watches out tinted windows of a mini van or other similar vehicle. Usually they are watching a residence or other structure from some distance away, waiting for the subject of interest to leave, come into view or conduct certain activities to be documented for later evaluation and/or prosecution. Law enforcement agents sit and watch for hours at a specific area, usually a door to a dwelling or a vehicle parked in the driveway waiting for activity or departure. This type of surveillance can go on for days causing eyestrain, fatigue and frustration.
Motion detection systems in use today are inaccurate over long distances for motion monitoring of a specific point on a specific target. Several systems offer sweeping detection of an entire area for the change in fields to detect movement. Some of these also have trigger mechanisms to start video recorders automatically. However, these devices are not self-contained and capable of being aimed or pointed at a specific target for detecting movement of a specific area only and generating a perceptible alert signal.
U.S. Pat. No. 6,700,528 to Christopher R. Williams relates to the detection of a wide area under observation. Specifically, ice flows in rivers or ice sheets or rubble fields. The portable laser device is mounted proximate the target surface with orientation to laterally and elevation to identify detection of movement. Therefore, this device is designed for the detection of a large area of mass including ice sheets flowing down rivers and the like. The system is then designed to contact a responsible party by means of cell phone signal or similar device. It is not designed to detect the specific movement of one small area not larger than 2 square feet.
U.S. Pat. No. 5,299,971 to Frank J. Hart describes an interactive tracking device for detecting intruders with a single quadruplex stationary passive infrared sensor. The sensor provides a signal to a microcontroller which drives a stepper motor to rotate additional sensors with narrower fields of view to more precisely determine the exact bearing of the intruder. When an intruder is verified, a camera and/or light are activated to record the intruder. This device is designed for a larger area and “sweeps” the covered area for movement and not designed to be aimed at a specific target of a small size to detect the precise movement necessary to avoid false alerts to the operator.
U.S. Pat. No. 5,299,971 to Frank J. Hart describes an interactive tracking device for detecting intruders with a single quadruplex stationary passive infrared sensor. The sensor provides a signal to a microcontroller, which drives a stepper motor to rotate additional sensors with narrower fields of view to more precisely determine the exact bearing of the intruder. When an intruder is verified, a camera or lights are activated to record the intruder. This device too is designed for a larger area and “sweeps” the covered area for movement and not designed to be aimed at a specific target of a small size to detect the precise movement necessary to avoid false alerts to the operator.
U.S. Pat. No. 5,757,004 to Donald R. Sandell & Wade Lee May 26, 1998 describes a motion detector with a lens-sensor mounting and adjustment arrangement that permits a user to adjust the effective range of the motion detector without alerting the sensor's sensitivity settings. The mounting arrangement provides for relative movement of the sensor in relation to the lens matrix through an adjustment accessible to the user. The primary use of this device is to detect movement in an “area” covered in the field by the sensor such as a room or portion of an outside yard perhaps. The sensitivity setting or range is to shorten the distance of the effective range and not necessarily making it more pin-point.
In other words, if you were to take a flashlight beam that gets wider and wider as it travels from the source, you would be simply shortening the distance in which it illuminates without altering how sensitive it is.
U.S. Patent Application Publication US2002/0060737, 2002 to Chun-Hsing Hsieh & Yuan-Jen Hsiao relates to the method of detecting motion for a digital camera. A method of detecting motion is described by capturing a first image and transferring it into a control device. This image is then stored with real-time gray scale values so that subsequent images taken can be compared to the first value to identify changes or movement. This device is not designed to be aimed at a specific target of small size.
Currently, law enforcement personnel conduct surveillance by simply watching their target. This is usually done from a safe distance with the help of binoculars, monocular, or some other similar instrument. This method of surveillance has multiple drawbacks. First of all, while watching their target, the surveillance personnel lose the ability to multitask. Secondly, the risk of missing an activity (at the target) becomes high when the personnel momentarily take their eyes off the target, or take a break. Third, through constantly monitoring the target, surveillance personnel can succumb to fatigue and frustration due to eye strain.
Hence, a strong need exists for a detection device that will consistently and accurately detect small movements on a target without continuous human monitoring.